package main

import (
	"encoding/json"
	"fmt"
	"math/rand"
	"os"
	"runtime"
	"sort"
	"strings"
	"sync"
	"sync/atomic"
	"time"

	"trial/ping/probing"
	"trial/ping/probing/icmp"
	"trial/ping/utils"

	"git.wecise.com/wecise/common/logger"
	"git.wecise.com/wecise/common/matrix/cfg"
	"git.wecise.com/wecise/common/matrix/util"
	"github.com/scylladb/go-set/strset"
)

type task struct {
	Server                   string `json:"server"`
	Timeout                  int    `json:"timeout"`
	NumberOfPings            int    `json:"numberofpings"`
	PacketInterval           int    `json:"packetinterval"`
	PacketSize               int    `json:"packetsize"`
	TypeOfService            int    `json:"typeofservice"` // Not used
	Retries                  int    `json:"retries"`       // Not used
	Poll                     int    `json:"poll"`
	FailureRetests           int    `json:"failureretests"`           // Not used
	RetestInterval           int    `json:"retestinterval"`           // Not used
	HostNameLookupPreference string `json:"hostnamelookuppreference"` // Not used
	Description              string `json:"description"`              // Not used
	Rule                     string `json:"rule"`
	PerfRule                 string `json:"perfrule"`
	TaskTime                 int64  `json:"tasktime"`
	Indicator                string `json:"indicator"`
}

type InputConfig struct {
	Poolsize     int    `toml:"poolsize"`
	Domain       string `toml:"domain"`
	StatInterval int    `toml:"stat_interval"`
}

type StatInfo struct {
	MinRtt    time.Duration
	MaxRtt    time.Duration
	AvgRtt    time.Duration
	LossCount int
	Count     int
}

type Input struct {
	*InputConfig
	ips           []string
	statinfomutex sync.Mutex
	statinfo      map[string]*StatInfo
	ipaddrs       map[string]string
	subSize       int
	workChan      chan *task
	stopChan      chan bool
	ds            *utils.DataStat
}

var mcfg = cfg.MConfig()

var allipsmutex sync.Mutex
var allips = strset.New()

/*
  poolsize=1000  同时ping的不同目标地址个数
  count=5        每轮ping的次数，每轮次产生一次统计结果，并切换目标地址
  interval=1000  两次ping之间的间隔，单位毫秒
  size=64        每次ping发送字节数，48～8192
  timeout=2      ping超时，单位秒
  detect=1ms     自动发现可ping通地址，并追加到 hosts.txt 文件，设置发现间隔时间需指定单位，如 ms,毫秒,us,微妙等，默认 0，不进行发现处理
*/

func main() {
	input := &Input{}
	input.statinfo = map[string]*StatInfo{}
	input.ipaddrs = map[string]string{}
	inputcfg := &InputConfig{
		Poolsize:     1000,
		StatInterval: 600,
	}
	inputcfg.Poolsize = mcfg.GetInt("poolsize", inputcfg.Poolsize)
	if detect_interval := mcfg.GetDuration("detect", 0); detect_interval != 0 {
		go detect(detect_interval)
	}
	fips := func() []string {
		xips := mcfg.GetStrings("ip|ping.ip", "")
		allipsmutex.Lock()
		for _, aips := range xips {
			allips.Add(strings.Split(aips, ",")...)
		}
		bs, _ := util.ReadFile("./hosts.txt")
		if len(bs) > 0 {
			xips := strings.Split(string(bs), "\n")
			for _, aips := range xips {
				allips.Add(strings.Split(aips, ",")...)
			}
		}
		if len(detectips) > 0 {
			util.WriteFile("./hosts.txt", []byte(string(bs)+"\n"+strings.Join(detectips, ",")), true)
			detectips = detectips[:0]
		}
		sips := allips.List()
		allipsmutex.Unlock()
		return sips
	}
	go func() {
		t := time.NewTicker(5 * time.Second)
		for {
			<-t.C
			input.ips = fips()
		}
	}()
	input.ips = fips()
	mcfg.OnChanged(func(cfg cfg.Configure) {
		input.ips = fips()
	})
	input.Init(inputcfg)
	go input.Run()
	go func() {
		last_count := 0
		t := time.NewTicker(1 * time.Second)
		for {
			select {
			case <-t.C:
				s := ""
				input.statinfomutex.Lock()
				ks := []string{}
				for k := range input.statinfo {
					ks = append(ks, k)
				}
				sort.Strings(ks)
				for i, k := range ks {
					v := input.statinfo[k]
					ip := input.ipaddrs[k]
					s += fmt.Sprintf("%-3d %-20s %15s : %-12s [%12s ~ %-12s] loss %d/%d\n", i, k, ip, v.AvgRtt, v.MinRtt, v.MaxRtt, v.LossCount, v.Count)
				}
				input.statinfomutex.Unlock()
				logger.Info("统计信息更新：", fmt.Sprint("\n", s))
				logger.Info(util.FormatDuration(time.Since(starttime)), "已经完成", pingcount, "次Ping操作，",
					"平均每秒", (int64(pingcount+1) * int64(time.Second) / int64(time.Since(starttime))), "次",
					"最近一秒", (pingcount - int32(last_count)), "次",
					"最大缓冲", icmp.MaxReceiveBufferUsed(),
				)
				last_count = int(pingcount)
			}
		}
	}()
	n := 0
	for {
		if n >= len(input.ips) {
			n = 0
			input.ips = append(input.ips, detectips...)
		}
		ip := input.ips[n]
		n++
		//
		ip = strings.TrimSpace(ip)
		if ip != "" {
			input.workChan <- &task{
				Server:         ip,
				Timeout:        mcfg.GetInt("timeout", 2),
				NumberOfPings:  mcfg.GetInt("count", 5), // 至少为2，小于2会导致不能正常结束
				PacketInterval: mcfg.GetInt("interval", 1000),
				PacketSize:     mcfg.GetInt("size", 64),
			}
		}
		// time.Sleep(1 * time.Millisecond)
	}
}

func (input *Input) Init(config interface{}) error {
	input.InputConfig = config.(*InputConfig)
	input.workChan = make(chan *task, input.Poolsize)
	input.stopChan = make(chan bool)
	input.subSize = runtime.GOMAXPROCS(0)
	return nil
}

func (input *Input) Run() (err error) {

	input.ds = utils.NewDataStat("service", "", input.StatInterval, input.Poolsize*2)
	defer input.ds.Close()
	go input.ds.Start()

	defer close(input.workChan)

	var wg sync.WaitGroup
	// Start worker
	// count := int32(0)
	// lpcmutex := sync.Mutex{}
	// lastprintcount := time.Now()
	for i := 0; i < input.Poolsize; i++ {
		go func(n int) {
			for t := range input.workChan {
				wg.Add(1)
				// Run task
				if e := input.send(t, n); e != nil {
					logger.Error("Send error:", e)
					input.ds.Send(1)
				} else {
					input.ds.Send(0)
				}
				wg.Done()
				// x := atomic.AddInt32(&count, 1)
				// lpcmutex.Lock()
				// printmsg := time.Since(lastprintcount) >= 1*time.Second
				// if printmsg {
				// 	lastprintcount = time.Now()
				// }
				// lpcmutex.Unlock()
				// if printmsg {
				// 	logger.Info("已经完成", x, "个目标的Ping操作")
				// }
			}
		}(i)
	}

	<-input.stopChan
	wg.Wait()

	return nil
}

var pingcount int32
var starttime = time.Now()
var printpingcountmutex sync.Mutex
var printpingcounttime = time.Now()

func (input *Input) send(t *task, workerNum int) error {
	hostname, _ := os.Hostname()
	var (
		status  = "success"
		message = "Pings Complete"
		m       = map[string]interface{}{
			"service":      "icmp",
			"monitorHost":  hostname,
			"host":         t.Server,
			"pollInterval": t.Poll,
			"taskTime":     t.TaskTime,
			"indicator":    t.Indicator,
		}
	)

	pinger, err := probing.NewPinger(t.Server)
	if err != nil {
		status = "failure"
		message = err.Error()
		sips := strset.New(input.ips...)
		sips.Remove(t.Server)
		input.ips = sips.List()
		logger.Error(err)
	} else {
		/*
			https://stackoverflow.com/questions/41423637/go-ping-library-for-unprivileged-icmp-ping-in-golang/41425527#41425527
			This library attempts to send an "unprivileged" ping via UDP. On linux, this must be enabled by setting
			sudo sysctl -w net.ipv4.ping_group_range="0   2147483647"
			If you do not wish to do this, you can set pinger.SetPrivileged(true) and use setcap to allow your binary using go-ping to bind to raw sockets (or just run as super-user):
			setcap cap_net_raw=+ep /bin/goping-binary
			getcap /bin/goping-binary to validate
		*/
		pinger.SetPrivileged(false)
		if t.NumberOfPings > 0 {
			pinger.Count = t.NumberOfPings
		} else {
			pinger.Count = 1
		}
		if t.PacketInterval > 0 {
			pinger.Interval = time.Millisecond * time.Duration(t.PacketInterval)
		}
		if t.PacketSize > 0 {
			pinger.Size = t.PacketSize
		}
		if t.Timeout > 0 {
			pinger.Timeout = time.Second * time.Duration(t.Timeout)
		} else {
			pinger.Timeout = time.Second * time.Duration(pinger.Count)
		}
		var (
			consecutiveFailures int
		)
		var recvMutex sync.Mutex
		var recvList = map[int]int{}

		pinger.OnSend = func(pkt *probing.Packet) {
			recvMutex.Lock()
			if recvList[pkt.Seq] != 0 {
				println("并发控制有问题")
			}
			recvList[pkt.Seq]++
			recvMutex.Unlock()
			input.statinfomutex.Lock()
			si := input.statinfo[t.Server]
			if si == nil {
				si = &StatInfo{}
				input.statinfo[t.Server] = si
			}
			input.ipaddrs[t.Server] = pkt.IPAddr.String()
			si.Count++
			input.statinfomutex.Unlock()
		}
		pingMsg := fmt.Sprintf("\nWoker %d PING %s (%s):\n", workerNum, pinger.Addr(), pinger.IPAddr())
		pinger.OnRecv = func(pkt *probing.Packet) {
			recvMutex.Lock()
			recvList[pkt.Seq]++
			recvMutex.Unlock()
			s := fmt.Sprintf("%s %d bytes from %s: icmp_seq=%d time=%v\n",
				time.Now().Format("15:04:05.000"), pkt.Nbytes, pkt.IPAddr, pkt.Seq, pkt.Rtt)
			pingMsg += s
			// fmt.Print(s)
			// printpingcount
			atomic.AddInt32(&pingcount, 1)
		}
		pinger.OnDuplicateRecv = func(pkt *probing.Packet) {
			recvMutex.Lock()
			recvList[pkt.Seq]++
			recvMutex.Unlock()
			s := fmt.Sprintf("%s %d bytes from %s: icmp_seq=%d time=%v (DUP!)\n",
				time.Now().Format("15:04:05.000"), pkt.Nbytes, pkt.IPAddr, pkt.Seq, pkt.Rtt)
			pingMsg += s
			// fmt.Print(s)
		}
		pinger.OnFinish = func(stats *probing.Statistics) {
			m["numberPackets"] = stats.PacketsSent
			m["averageRTT"] = stats.AvgRtt.Milliseconds()
			if stats.PacketsSent == 0 {
				m["respondPercent"] = 1
			} else {
				m["respondPercent"] = stats.PacketsRecv / stats.PacketsSent * 100
			}
			//m["failureRetests"] = ?

			s := fmt.Sprintf("--- %s ping statistics ---\n", stats.Addr)
			s += fmt.Sprintf("%d packets transmitted, %d packets received, %v%% packet loss\n",
				stats.PacketsSent, stats.PacketsRecv, stats.PacketLoss)
			s += fmt.Sprintf("round-trip min/avg/max/stddev = %v/%v/%v/%v\n",
				stats.MinRtt, stats.AvgRtt, stats.MaxRtt, stats.StdDevRtt)
			pingMsg += s
			// fmt.Print(s)
			input.statinfomutex.Lock()
			si := input.statinfo[t.Server]
			if si == nil {
				si = &StatInfo{
					MinRtt:    stats.MinRtt,
					MaxRtt:    stats.MaxRtt,
					AvgRtt:    stats.AvgRtt,
					LossCount: 0,
					Count:     0,
				}
				input.statinfo[t.Server] = si
				input.ipaddrs[t.Server] = stats.IPAddr.String()
			}
			if stats.MinRtt > 0 && (si.MinRtt == 0 || stats.MinRtt < si.MinRtt) {
				si.MinRtt = stats.MinRtt
			}
			if stats.MaxRtt > si.MaxRtt {
				si.MaxRtt = stats.MaxRtt
			}
			si.AvgRtt = stats.AvgRtt
			si.LossCount += stats.PacketsSent - stats.PacketsRecv
			input.statinfomutex.Unlock()
		}
		m["requestTime"] = time.Now().UnixNano() / int64(time.Millisecond)
		if err = pinger.Run(); err != nil {
			status = "failure"
			message = err.Error()
			logger.Errorf("Ping error: %v", err)
		} else {

		}
		m["responseTime"] = time.Now().UnixNano() / int64(time.Millisecond)

		var failCount, totalFailCount int
		recvMutex.Lock()
		for i := range recvList {
			if recvList[i] < 2 {
				failCount++
				message = "Packet loss"
				totalFailCount++
			} else {
				failCount = 0
			}
			if failCount > consecutiveFailures {
				consecutiveFailures = failCount
			}
			pingMsg += fmt.Sprintf("icmp_seq:%d %t\n", i, (recvList[i] >= 2))
		}
		// logger.Debug(pingMsg)
		m["consecutiveFailures"] = consecutiveFailures
		if totalFailCount == len(recvList) {
			message = "ICMP echo failed"
		}
		recvMutex.Unlock()
	}

	// Special
	m["returnStatus"] = status
	m["message"] = message

	b, err := json.Marshal(m)
	if err != nil {
		logger.Fatal(err)
	}

	protocolMsg := map[string]interface{}{
		"protocol": true,
		"output":   b,
		"attr":     map[string]string{"previous_key": input.Domain + "_" + t.Server},
	}
	b, err = json.Marshal(protocolMsg)
	if err != nil {
		logger.Fatal(err)
	}

	return nil
}

var detectips = []string{}

func detect(detect_interval time.Duration) {
	t := time.NewTicker(detect_interval)
	for {
		<-t.C
		randip := fmt.Sprintf("%d.%d.%d.%d", 1+rand.Intn(254), 1+rand.Intn(254), 1+rand.Intn(254), 1+rand.Intn(254))
		allipsmutex.Lock()
		has := allips.Has(randip)
		allipsmutex.Unlock()
		if !has {
			if detectip(randip) {
				allipsmutex.Lock()
				detectips = append(detectips, randip)
				allipsmutex.Unlock()
			}
		}
	}
}

func detectip(addr string) (ok bool) {
	pinger, err := probing.NewPinger(addr)
	if err != nil {
		return false
	}
	pinger.SetPrivileged(false)
	pinger.Count = 1
	pinger.Interval = 200 * time.Millisecond
	pinger.Size = 32
	pinger.Timeout = 1 * time.Second
	pinger.OnRecv = func(pkt *probing.Packet) {
		ok = true
	}
	pinger.Run()
	return
}